Method and an apparatus of actively sensing neuronal firing frequency at a functional site in a brain

Abstract

The present application provides a method and an apparatus of actively sensing a neuronal firing frequency at a functional site in a brain, the method comprising: generating a varying electromagnetic field and acting a near field of the generated electromagnetic field on a targeted brain functional site; sensing the alteration of the electromagnetic field at the targeted brain functional site; and determining a variation frequency of the alteration of the electromagnetic field at the targeted brain functional site as the neuronal firing frequency at the targeted brain functional site.

The invention claimed is: 
     
       1. A method of actively sensing a neuronal firing frequency at a functional site in a brain, comprising:
 generating a varying electromagnetic field and acting a near field of the generated electromagnetic field on a targeted brain functional site; 
 sensing alteration of the electromagnetic field at the targeted brain functional site; and 
 determining a variation frequency of the alteration of the electromagnetic field at the targeted brain functional site as the neuronal firing frequency at the targeted brain functional site, 
 wherein the near field is defined by the distance d of the generated varying electromagnetic field from an antenna generating the electromagnetic field, the largest dimension D of the antenna, as well as the wavelength λ of the generated electromagnetic field in vacuum in the relationship of 
 
       
         
           
             
               0 
               < 
               d 
               ≤ 
               
                 0.62 
                 * 
                 
                   
                     
                       
                         D 
                         3 
                       
                       λ 
                     
                   
                   . 
                 
               
             
           
         
       
     
     
       2. The method of  claim 1 , wherein the frequency of the generated varying electromagnetic field in vacuum is such that the wavelength of the electromagnetic field at the brain functional site matches a dimension of the targeted brain functional site. 
     
     
       3. The method of  claim 1 , wherein the waveform of the varying electromagnetic field is alternating or pulsed. 
     
     
       4. The method of  claim 1 , wherein,
 the alteration of the electromagnetic field in the targeted brain functional site is a phase alteration and is determined by comparing the phase of the sensed electromagnetic field at the brain functional site with the phase of the generated electromagnetic field, or 
 the alteration of the electromagnetic field in the targeted brain functional site is an amplitude alteration and is determined by comparing the amplitude of the sensed electromagnetic field at the brain functional site with the amplitude of the generated electromagnetic field. 
 
     
     
       5. The method of  claim 1 , wherein the alteration of the electromagnetic field at the targeted brain functional site is sensed by a first antenna generating the electromagnetic field acting on the brain functional site or by a second antenna separate from the first antenna. 
     
     
       6. The method of  claim 1 , wherein the functional site in the brain is the anterior cingulate cortex (ACC) for pain perception, and a degree of pain percept in the brain is determined from the determined neuronal firing frequency at the ACC together with a calibration between the neuronal firing frequency and an intensity of pain. 
     
     
       7. The method of  claim 1 , wherein the functional site in the brain is the brain site for intention to act, including the prefrontal cortex and motor cortex. 
     
     
       8. An apparatus for actively sensing a neuronal firing frequency at a functional site in a brain, comprising:
 means for generating a varying electromagnetic field and acting a near field of the generated electromagnetic field on a targeted brain functional site; 
 means for sensing alteration of the electromagnetic field at the targeted brain functional site; and 
 means for determining a variation frequency of the altercation of the electromagnetic field at the targeted brain functional site as the neuronal firing frequency at the targeted brain functional site, 
 wherein the near field is defined by the distance d of the generated varying electromagnetic field from an antenna generating the electromagnetic field, the largest dimension D of the antenna, as well as the wavelength λ of the generated electromagnetic field in vacuum in the relationship of 
 
       
         
           
             
               
                 0 
                 < 
                 d 
                 ≤ 
                 
                   
                     
                       D 
                       3 
                     
                     λ 
                   
                 
               
               , 
             
           
         
       
     
     
       9. The apparatus of  claim 8 , wherein the frequency of the generated varying
 electromagnetic field in vacuum is configured such that the wavelength of the electromagnetic field at the 
 brain functional site matches the dimension of the targeted brain functional site. 
 
     
     
       10. The apparatus of  claim 8 , wherein the waveform of the varying
 electromagnetic field is alternating or pulsed, or the power of the varying electromagnetic field is 
 varying at a preset modulated frequency. 
 
     
     
       11. The apparatus of  claim 8 , wherein:
 the alteration of the electromagnetic field in the targeted brain functional site is a phase 
 alteration and is determined by comparing the phase of the sensed electromagnetic field at the 
 brain functional site with the phase of the generated electromagnetic field, or 
 the alteration of the electromagnetic field in the targeted brain functional site is an 
 amplitude alteration and is determined by comparing the amplitude of the sensed electromagnetic field at the brain functional site with the amplitude of the generated electromagnetic field.